I just bought a Powermaster 200amp with adjustable voltage regulator. Going to set it at 14.5v and hopefully it will fix that issue.
I know the extra amps wont do anything for the voltage but my Nav/Stereo system will like it.
Fuel pressure and Voltage
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I just bought a Powermaster 200amp with adjustable voltage regulator. Going to set it at 14.5v and hopefully it will fix that issue.
I know the extra amps wont do anything for the voltage but my Nav/Stereo system will like it.
RmvBfrFlght
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- Sep 28, 2007
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A TA62 turbo is enough for 650 to 675 HP.
A single GSS340 pump at 12 volts and 70 psi (43 psi fuel pressure + 27 psi boost) flows 45 gallons per hour, or 270 #/hr (@ 6 # per gallon).
A single GSS340 pump at 13.5 volts and 70 psi (43 psi fuel pressure + 27 psi boost) flows 52 gallons per hour, or 312 #/hr (@ 6 # per gallon).
Neither of which will support 650 HP. Need a better pump or a dual GSS340 set up.
Flow data is from various charts posted here in the past.
RemoveBeforeFlight
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That's because the fuel pump was not being driven with enough voltage to supply the correct amount of fuel to the pump.
The voltage drop is the issue not the file pump or the alky pump. Get that solved and the car will be happy. And reset the alky set point to 8 psi. That will goof things up if you don't.
The booster is $70 new and I picked up a used one for $20 so you can do it too.
Good luck.
The voltage drop is the issue not the file pump or the alky pump. Get that solved and the car will be happy. And reset the alky set point to 8 psi. That will goof things up if you don't.
The booster is $70 new and I picked up a used one for $20 so you can do it too.
Good luck.
The generator is dropping voltage. It's not supposed to do this. It has to be repaired or replaced to stop that. A volt booster might an likely would bring the volts up to 16 while it is activated,but the generator has a problem and needs to be fixed.
A single pump at 16 volts is plenty for 20 lbs of boost and more. Lets get this thing running good at 20 lbs of boost then ,when that becomes boring we can up the boost,watch the O2s,and see how far one pump and Alky can go.
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My car runs 20 psi on the street and its pretty quick. You won't make it to 16 psi on a single pump. you will pop head gaskets for sure.
The generator you have will work fine. Get the volt booster that solves your problem. The booster full fields the alternator at 80 % throttle or more. That in turn drives the pumps.
The generator you have will work fine. Get the volt booster that solves your problem. The booster full fields the alternator at 80 % throttle or more. That in turn drives the pumps.
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Like many others here, for years I had thought that a hot wire kit solved our voltage problem of supplying enough electrical power to the in-tank pump? 
After a few disasters with faster GN's, and then building some race cars with an external fuel pump, we found the hot wire is only part of the solution.
If you run a 10 ga. wire to the pump connector, you still have a massive voltage drop through the connectors, external and internal, and the small gauge wire in the tank. So if you have 15 volts at the connector, you still do NOT have 15 volts at the pump.
On top of that, the weak ground wire is soldered to the pump hanger and then goes to the chassis. This is a horrible situation as the frame is NOT a good ground as there is massive resistance in this path back to the battery.
The fuel relay, or relays, in our race cars are wired DIRECTLY to the battery, both positive and negative connections.
A DC circuit will only conduct the electrical power that will be passed by the weakest "link". So a 10 ga. supply with 15 volts with a 16 ga. return is limited to the capacity of the smallest wire or resistance in a connector.
Certainly published fuel pump flow charts are compiled with data from closely controlled lab conditions, not on a car. So if you use their info in your car, you could be far away from what is needed to satisfy the fuel supply needs of your engine.
Is there any need to mention that the wiring, connectors, relays and other stock items we are using are at least 25 years old, and like us, they deteriorate with age!
After a few disasters with faster GN's, and then building some race cars with an external fuel pump, we found the hot wire is only part of the solution.
If you run a 10 ga. wire to the pump connector, you still have a massive voltage drop through the connectors, external and internal, and the small gauge wire in the tank. So if you have 15 volts at the connector, you still do NOT have 15 volts at the pump.
On top of that, the weak ground wire is soldered to the pump hanger and then goes to the chassis. This is a horrible situation as the frame is NOT a good ground as there is massive resistance in this path back to the battery.
The fuel relay, or relays, in our race cars are wired DIRECTLY to the battery, both positive and negative connections.
A DC circuit will only conduct the electrical power that will be passed by the weakest "link". So a 10 ga. supply with 15 volts with a 16 ga. return is limited to the capacity of the smallest wire or resistance in a connector.
Certainly published fuel pump flow charts are compiled with data from closely controlled lab conditions, not on a car. So if you use their info in your car, you could be far away from what is needed to satisfy the fuel supply needs of your engine.
Is there any need to mention that the wiring, connectors, relays and other stock items we are using are at least 25 years old, and like us, they deteriorate with age!
Yes it will. Now,put that generator on and set it to 14.5 volts and watch your Scanmaster. The volts won't fall which means your pump will get more voltage where it needs it,Up stairs. At a minimum you'll log less of a pressure loss and it might be enough to get you where you need to be. Do this step next,then we can evaluate the results and plan the next step. Again, you have plenty of pump to get you to 22lbs of boost. We just need to give the pump what it needs to do its job,Volts.
Nick- I sent you a PM regarding my volts at the pump with key on. I forgot to mention that I do have a Casper volt booster. If anybody else has suggestions.....I have over 12 volts at battery (car not running) and the same volts at the alternator. Back at the pump, the hotwire shows 5.7 volts, as does the factory wire. The only thing between the hotwire connector at the pump and the alternator is a fuse holder and a relay (and about 10 feet of wire). Maybe I'm doing something wrong. When I connected the volt meter to the same ground as my amps in the trunk, there was no difference in volts at the pump (still 5.7). However, I think the ground is good, as my amps are seeing 11.8 volts, as is the trunk light. Again this is with the motor off, key "on".
I just to spoke with Nick on the phone and he set me straight. When you turn the key to "on", the pump runs for a few seconds (like 5 seconds) and then shuts off. My problem was that I was checking the voltage at the pump long after this 5 second period. So I will check it when I find a friend to turn the key on with me back at the pump with my voltmeter ready. The other way is to back probe the fuel pump connection with the car running.
Check it with the car running.
That is as good as it gets.
I screw the ground wire to the passenger side gas tank strap anchor,using the body as a ground wire. There's a wire that connects the motor to the body,the body to the battery,and the battery to the motor.
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